I bring it back all the time! But I have GIAC flash and I think they only raise the rev by 50-100 something like that.

I can tell you that itself is grounds to deny warranty even if nothing related to that is found. They will try to void whatever they can it seems. And no shit luck if BMW Asia happens to be the one to see your car. More often than not, look out for this guy Ralf Beck from BMW Asia. If he is the one looking at your car, you might as well try to solve it yourself. HONESTLY.